1.Field of the Invention
The present invention relates to a photographic enlarger which carries out a printing operation using exposure data fed by an external analyzer, which analyzer is capable of detecting a condition of the optical system thereof, for example, the magnification or the aperture size.
2. Description of the Prior Art
An enlarger which prints a film using exposure data fed directly from an external analyzer such as VCNA (Video Color Negative Analyzer) is known. Said enlarger memorizes the difference between exposure data to make a best print (hereinafter, referred to as "the best print data") obtained by said enlarger itself and that obtained by the external analyzer and converts the exposure data fed by the external analyzer in accordance with the memorized difference so that the exposure data may be suitable for said enlarger.
However, the above-mentioned enlarger is constructed on the assumption that the condition of the optical system of the enlarger is not changed from the best print condition. Therefore, the enlarger cannot function well in a case where the condition of the optical system is changed, for example, in a case where the magnification or the aperture is changed.
On the other hand, another type of enlarger is shown in U.S. Pat. No. 4,469,437. Even if the condition of the optical system is changed from the best print condition, the enlarger in U.S. Pat. No. 4,469,437 can obtain the best print data without any complicated process.
However, said enlarger is constructed for private use, and cannot carry out a mass printing operation in accordance with the exposure data fed by an external analyzer.